Hajra Dipasree, Rajmani Raju S, Chaudhary Ayushi Devendrasingh, Gupta Shashi Kumar, Chakravortty Dipshikha
Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India.
Centre of Infectious Disease Research, Indian Institute of Science, Bangalore, India.
Elife. 2024 Dec 18;13:RP93125. doi: 10.7554/eLife.93125.
Sirtuins are the major players in host immunometabolic regulation. However, the role of sirtuins in the modulation of the immune metabolism pertaining to salmonellosis is largely unknown. Here, our investigation focussed on the role of two important sirtuins, SIRT1 and SIRT3, shedding light on their impact on intracellular 's metabolic switch and pathogenesis establishment. Our study indicated the ability of the live Typhimurium to differentially regulate the levels of SIRT1 and SIRT3 for maintaining the high glycolytic metabolism and low fatty acid metabolism in . Perturbing SIRT1 or SIRT3 through knockdown or inhibition resulted in a remarkable shift in the host metabolism to low fatty acid oxidation and high glycolysis. This switch led to decreased proliferation of in the macrophages. Further, -induced higher levels of SIRT1 and SIRT3 led to a skewed polarization state of the macrophages from a pro-inflammatory M1 state toward an immunosuppressive M2, making it more conducive for the intracellular life of . Alongside, governing immunological functions by modulating p65 NF-κB acetylation, SIRT1, and SIRT3 also skew induced host metabolic switch by regulating the acetylation status of HIF-1α and PDHA1. Interestingly, though knockdown of SIRT1/3 attenuated proliferation in macrophages, in in vivo mice model of infection, inhibition or knockdown of SIRT1/3 led to more dissemination and higher organ burden, which can be attributed to enhanced ROS and IL-6 production. Our study hence reports for the first time that modulates SIRT1/3 levels to maintain its own metabolism for successful pathogenesis.
沉默调节蛋白是宿主免疫代谢调节的主要参与者。然而,沉默调节蛋白在沙门氏菌病相关免疫代谢调节中的作用在很大程度上尚不清楚。在此,我们的研究聚焦于两种重要的沉默调节蛋白SIRT1和SIRT3的作用,揭示它们对细胞内代谢转换和发病机制建立的影响。我们的研究表明,活的鼠伤寒沙门氏菌能够差异性地调节SIRT1和SIRT3的水平,以维持其高糖酵解代谢和低脂肪酸代谢。通过敲低或抑制来干扰SIRT1或SIRT3会导致宿主代谢显著转变为低脂肪酸氧化和高糖酵解。这种转换导致巨噬细胞中其增殖减少。此外,其诱导的较高水平的SIRT1和SIRT3导致巨噬细胞的极化状态从促炎的M1状态偏向免疫抑制的M2状态,使其更有利于其在细胞内生存。同时,SIRT1和SIRT3通过调节p65 NF-κB乙酰化来控制免疫功能,还通过调节HIF-1α和PDHA1的乙酰化状态来使诱导的宿主代谢转换发生偏移。有趣的是,尽管敲低SIRT1/3会减弱其在巨噬细胞中的增殖,但在体内感染小鼠模型中,抑制或敲低SIRT1/3会导致更多的扩散和更高的器官负荷,这可归因于活性氧和白细胞介素-6产生的增加。因此,我们的研究首次报道其调节SIRT1/3水平以维持自身代谢从而成功致病。